Credible Forecasts Research Articles

Ohio Long-Distance Travel Model

Credible forecasts of long-distance travel are an important tool for evaluating proposed intercity transportation improvements, including intercity highway and transit projects. Although researchers have studied the topic and have developed frameworks for modeling long-distance travel behavior, these research models have not been integrated into comprehensive model systems used for a wide range of applications. This paper presents a long-distance travel model that bridges the gap between research and practice. It is based on a rigorous behavioral framework that models the unique aspects of long-distance travel, such as a less regular frequency of trips and a different set of modal alternatives. The model structure includes the choice of whether to travel, the selection of the days on which to travel, scheduling to a specific time of day, destination choice, and mode choice. The model is sensitive to important descriptive variables, including the demographic characteristics of travelers, the attractiveness of possible destinations, and the levels of service of air, transit, and highway networks. It has been successfully implemented as part of the Ohio statewide model, which also features an advanced tour-based model of short-distance travel. Through this integration, it allows for behavioral consistency within the entire model system and competition among all travelers for transportation capacity. Lessons are learned about the data needs and research needs to further improve long-distance travel models.

Capital efficiency, its measurements and its role in regulatory reviews of utility industries: Lessons from developed and developing countries

Designing regulatory regimes that incentivise the delivery of agreed capex at as low a cost as possible has proven relatively straight-forward when it is possible to establish credible forecasts of the necessary capex and its associated cost. Greater problems arise when there is uncertainty about what capex is needed, when it may be needed and how much it will cost. Yet it is still possible to establish incentive based systems for regulating capex with some or all the characteristics that create uncertainty. This paper explores some of the issues related to incentive based regulation of capex and how flexible approaches can be developed to handle the uncertainty inherent in certain types of capex. Examples of incentive based systems are also provided.

How to Predict Companies' Future Actions-A Three-Part Series

Too often businesses concentrate on historical rather than prospective business actions. Only by anticipating the future actions and capabilities of leading companies can yo take timely action and leapfgrog into positions of superiority

Market-Based Framework for Forecasting Parking Cost in Traditional and Microsimulation Modeling Applications

Parking cost is an important variable in determining mode choice, yet it receives little attention in most travel forecasting models. This paper presents a framework for modeling parking supply and cost that has three advantages over most parking cost models: a market-based approach is used to equilibrate parking demand with parking supply; actual parking costs paid by groups of travelers rather than average parking costs are estimated for each transportation analysis zone; and estimates are made from longitudinal data. This framework has been applied successfully in a traditional four-step travel model and is being used in practice. It also provides additional opportunities for application in a segmented manner or in concert with a microsimulation modeling approach. Mode choice results based on aggregate and segmented applications of the framework are substantially different. Improved forecasting of parking costs should be an important consideration in any new model development. In recent years, substantial efforts have been focused on household interactions and activity modeling. Although the understanding of travel behavior has improved substantially, the improved techniques still depend on good input data for credible forecasts.

Market-Based Framework for Forecasting Parking Cost in Traditional and Microsimulation Modeling Applications

Parking cost is an important variable in determining mode choice, yet it receives little attention in most travel forecasting models. This paper presents a framework for modeling parking supply and cost that has three advantages over most parking cost models: a market-based approach is used to equilibrate parking demand with parking supply; actual parking costs paid by groups of travelers rather than average parking costs are estimated for each transportation analysis zone; and estimates are made from longitudinal data. This framework has been applied successfully in a traditional four-step travel model and is being used in practice. It also provides additional opportunities for application in a segmented manner or in concert with a microsimulation modeling approach. Mode choice results based on aggregate and segmented applications of the framework are substantially different. Improved forecasting of parking costs should be an important consideration in any new model development. In recent years, substantial efforts have been focused on household interactions and activity modeling. Although the understanding of travel behavior has improved substantially, the improved techniques still depend on good input data for credible forecasts.

Forest-level models and challenges for their successful application

Significant advances have been made that integrate landscape issues in forest-level models. These advanced models are designed to simulate and evaluate economic, ecological, and social goals that are included in the management of forests. The application of multiple-objective heuristics such as tabu search and simulated annealing, combined with remarkable advances in computing power, now allows us to explore highly complex management scenarios over long time horizons and over vast geographic scales. While the power of these decision support systems is highly appealing, and even intoxicating, we still face three sobering challenges on the path towards generating credible forecasts. First, advanced data acquisition and data management systems are needed to support these systems. Data management systems must have high storage capacity, be capable of rapid updates, and accommodate a seemingly endless demand for queries from customers, government agencies, and the public. Planning is an interdisciplinary, hierarchical process, and team members have different data demands, depending on where they fit in the hierarchy. Second, the models must be verified. Multiple-objective models have dozens of parameters, and when these are combined with random search techniques, they become difficult to understand and replicate. Thorough sensitivity analysis is needed to test model parameters, goal weights, and assumptions of uncertainty. Finally, our ability to formulate and run large-scale, long-term forecasting models often exceeds the scientific credibility of the data, especially for complex forest ecosystems. In the absence of critical thinking, such powerful models can become dangerous weapons.

Modelling the impact of dewatering in the Lower Greensand aquifer, Surrey

Abstract ARC (Southern) intend to extend and deepen working from two quarries in the Folkestone Formation, near Reigate in Surrey, UK. During the planning process, credible forecasts of the impact of future dewatering strategies are required to reassure the concerns of the Environment Agency, environmentalists and local water users. A hydrogeological and modelling study was carried out to investigate the present groundwater flow in the Lower Greensand aquifer, and to forecast the future pumping rates required to maintain dry excavations, the impact of further dewatering on groundwater levels and quality, and water levels after the end of quarrying. At the site, the Folkestone Formation consists of two discrete sand horizons, separated hydraulically by a clay layer, which supports head differences of 10 m near the quarries. Apart from ARC's recent monitoring of flows and water levels, very limited information on the aquifer was available, but the problem was minimized by careful calibration of the model for the three years with the most data. The results were used to modify working plans to minimize the impact on the surrounding aquifer and to support ARC's application for planning permission to extend the quarries.

Oil Production Forecasts for the year 2020 Suggest that Reserves will be Larger in 2020 than in 1998

The US DOE/EIA prepares the most detailed, coherent and credible forecasts of energy supply and demand in the USA through to the year 2020. These are the forecasts on which national and international energy policy is made and on which commercial decisions are taken.

Coastal Frontogenesis and Precipitation during ERICA IOP 2

Abstract The inverted trough and coastal front that occurred during ERICA IOP 2 were studied in order to assess the ability of an operational mesoscale model, the Canadian Regional Finite Element Model, to provide credible forecast guidance concerning the regional distribution of precipitation associated with such events. The observed distribution of the heaviest precipitation was dependent on the orientation and inland penetration of the coastal front and its associated (geostrophic) frontogenetic forcing, although considerable local variability was evident. The observations indicate that the front penetrated inland along a line west of Boston through east-central Connecticut. The model, which performed exceptionally well in forecasting the eventual development of the main cyclone, correctly forecast the existence and general location of the inverted trough and coastal front and thereby gave indications of the development of heavy snowfall within the coastal region of New York–New England 18–24 h in adva...

Telling Weathermen When to Worry

Telling Weathermen When to Worry

Remote Sounding of Atmospheres

One of the first applications proposed for earth‐orbiting satellites was the observation of the atmosphere. A glance at any television weather report shows how far things have come. Pictures taken from geostationary orbit show cloud distributions over a large part of the globe, and credible forecasts utilizing satellite temperature soundings extend several days into the future. These data have had a profound influence on research as well. A recent article (“Breaking planetary waves in the stratosphere,” by M. E. Mclntyre and T. N. Palmer, Nature, vol. 303, pp. 593–600, 1983.) stated that “Satellite‐borne IR radiometers are turning the Earth's stratosphere into one of the best available outdoor laboratories for observing the large scale dynamics of a rotating heterogeneous fluid under gravity.” Remote sounding data have revolutionized our understanding of the atmospheres of this and other planets.

Forecasting the impact of public policies

Indicators, system variables and other objective measures have long been used in forecasting to produce trends. The method of forecasting trends has developed from implied forecasting, to judgmental and concensus methods, to various extrapolative and probabilistic techniques. These methods have been used to develop more likely and credible forecasts for trends. This paper describes a new forecasting method to aid decision-makers in identifying, analyzing, and evaluating the various policy options available to them.

Environment and the transport planner

The transport planner sees the problem of the conflict between the motor car and the environment in today's conditions and foresees how the problems are going to grow in the future. He strives to provide the means to satisfy the growing demand for road space but he is conscious that his solutions can be, in themselves, damaging to some aspects of the quality of life. He faces the dilemma of deciding where to strike the balance between these conflicting considerations. The planner has to suggest this point of balance; in order to do so, he must be able to make logical and credible forecasts of the results of different kinds of transport policy and he must be able to present these clearly to the politicians and the public. So that he can produce such forecasts, he has constantly to improve and refine his techniques; the paper indicates some of the ways in which this is being done in Great Britain today.